Qatar said on Wednesday that a new blacklist released by Saudi Arabia and its allies came as a "disappointing surprise" in a diplomatic crisis that has split the Gulf.

The four Arab governments named 18 organisations and individuals on Tuesday that they accused of links with extremism and Qatar.

The move by Saudi Arabia, the United Arab Emirates, Egypt and Bahrain came despite mounting international pressure to compromise in their weeks-old boycott of their fellow US ally.

Qatari government communications director Sheikh Saif bin Ahmed Al-Thani official said the blacklist had no basis in fact and was aimed at stripping the emirate of its sovereignty.

"It comes as a disappointing surprise that the blockading countries are still pursuing this story as part of their smear campaign against Qatar," he said in a statement.

"This latest list provides further evidence that the blockading countries are not committed to the fight against terrorism.

"All individuals with links to terrorism in Qatar have been prosecuted. We encourage the blockading countries to spend less time on drafting these fabricated lists and more time on implementing measures to counter the threat of extremism in their own countries."

The four governments issued a previous blacklist of 59 individuals and 12 groups last month. Sheikh Saif said it had been "widely rejected by the international community".

Saudi Arabia and its allies have been boycotting Qatar since June 5 in the region's worst diplomatic crisis in years.

They sealed the emirate's only land border, ordered its citizens to leave and closed their airspace and waters to Qatari flights and shipping.

They demanded that Qatar break its longstanding ties with the Muslim Brotherhood, blacklisted as a "terror group" by the four governments although not by the international community.

They also demanded that it close broadcasting giant Al-Jazeera and a Turkish military base, and fall in line with Saudi-led policy in the region, particularly towards Iran.

Qatar has dismissed the demands as a violation of its sovereignty and has received significant support from its ally Turkey.

United States Secretary of State Rex Tillerson, who last week spent four days in the region trying to broker a settlement of the crisis, has voiced satisfaction with Qatar's efforts to address any suspicion of terror funding.

But after talks with European Union diplomatic chief Federica Mogherini on Tuesday, Egyptian Foreign Minister Sameh Shoukry warned that the four governments would accept no compromise in their dispute with Qatar.

"We cannot compromise with any form of terrorism, we cannot compromise or enter into any form of negotiations," Shoukry told a press conference.